Wash arm arrangements comprising a central arm onto which an additional second arm, herein after referred to as a satellite arm, is arranged on an outer portion of the central arm are known. Typically, the central arm is connected to a central shaft which serves as a cleaning liquid and rinsing liquid supply duct arranged for feeding the wash arm arrangement with pressurized cleaning liquid during operation of the dishwasher. The central arm can be positioned either at the bottom, in the middle, or at the ceiling of the dishwasher treatment chamber. The satellite arm is mounted with its center to a second shaft for feeding the satellite arm with cleaning liquid during operation of the dishwasher, which second shaft is arranged on an outer end of the central arm. Nozzles having different spray angles for covering a washing area of the treatment chamber with cleaning liquid and/or for driving the spray arm are typically arranged on the satellite arm and on the central arm. When the cleaning liquid is released during operation a thrust is created moving both arms in circles about their individual axis of rotation.
A wash arm arrangement according to this type of known wash arm arrangements is disclosed in U.S. Pat. No. 5,477,874, in which wash arm arrangement a set of first jetting openings, i.e. nozzles, arranged on a first end portion of a first arm, being the central arm, is arranged for jetting cleaning liquid obliquely along approximately the tangent of its rotation locus, driving the central arm in a clockwise direction, while simultaneously jetting cleaning liquid towards the dishes. Further, a second set of jetting openings arranged on a second arm, being the satellite arm, is arranged for jetting cleaning liquid obliquely along approximately the tangent of its rotation locus, driving the second arm in a counterclockwise direction, while simultaneously jetting cleaning liquid towards the dishes. The second arm is arranged on a second end portion of the first arm. The set of jetting openings arranged on the first arm, and the set of jetting openings arranged on the second arm are further arranged to provide respective reaction forces on their respective sides of the first arm which cause momentum on the first arm that are balanced in the horizontal direction and with respect to their respective distances from the rotation center of the first arm, such that respective momentums on the first arm caused by the jetting from the first and second set of nozzles towards the dishes are balanced. Thereby momentums directed in a direction opposite to the dishes generated on the first arm are balanced, wherein the first and second arm rotate smoothly.